Discussion on Uncertainty Management in Power Systems

The power grids are continuously exposed to numerous sources of uncertainties which threaten the reliable and secure supply of electricity. These uncertainties are mainly due to the occurrence of contingencies and more recently the high penetration of intermittent renewables. Managing uncertainties in power systems regarding the system security has received many attentions from power engineering communities using deterministic (e.g. N-1 criteria) and probabilistic (e.g. stochastic and robust) optimization approaches. These optimization methods aim to obtain a balance between the economy and security. In this respect, the value of security can be assessed in terms of risk. The risk is defined as the sum of the product of the consequence and probability of a given set of events. The evaluation of risk should be performed carefully in order to consider the high-probability/low-impact scenarios as well as the low-probability/high-impact ones. It is worth noting that the evaluation of the risk of low probable scenarios, with a certain accuracy level, is computationally much more difficult and time consuming.